Improvement in engraving-blocks



G. G. SBTOHBLL. Engraving-Blocks.'

Patented May 21, 1 87'8.,

No. 203,856l

UNTTED STATEs PATENT OEEIGE.

GEORGE C. SETCHELL, OF NORWICH, CONNECTICUT.

IMPROVEMENT IN ENGRAVING-BLOCKS.

Specification forming part of Letters Patent No. 203,856, dated May 21,1878; application filed March 21, 1877.

sents my mode of constructing blocks, eitherV out of new or old wood, ofdouble thickness, and the lower view represents the nished block, whichis produced by splitting the double-thick blocks through the middleofthe box-wood, as shown by the dotted lines in the drawing, and joiningthe sections edge to edge.

A represents the box-wood upper portion of my improved block; B, thecheap wood backing, and C the splines which should be used to strengthenthe joints between the sections of a finished block.

In utilizing old blocks I first dress off all the engraved portion, andalso the back side of the block, until a smooth plane surface is reachedon both sides of the box-wood; but in case new box-wood is used, it isfirst sawed about half the standard thickness of engravers blocks, anddressed off in the same manner.

I next glue firmly upon each -side of this boxwood center a cheap woodbacking, of mahogany or other suitable wood, which has been previouslydressed, so as to make strong gluejoints. Afterthe glue-jointshavebecome thoroughly set, these double-thick blocks are divided throughtheir box-wood central layer, and then their edges are dressed off andgrooves cut in the coarse wood backing for the insertion of splines,after which these sections are glued together in the ordinary manner, toform engravers blocks `of any required dimensions,

i, it never before having been practicable to obmainder a comparativelyvery cheap wood back is used, thus very largely reducing the expense.

Again, my improved blocks are much stronger than the ordinary box-woodblocks now in use, for the glue-joint between the box-wood top and thecheap wood back, owing to the glue entering the end grain of the wood inboth, and the large surface thereof, is abundantly strong, and thereforemy block is quite as good as a block of solid box-wood; a great increaseof strength is derived from the glue adhering more closely to the edgeof the coarse wood back than to the edge of the box-wood; and, besides,the splines will adhere much stronger in the grooves of the backing thanin the box-wood as ordinarily used. Thus iinished engravers blocks areproduced which, besides the great advantage of cheapness, have also theadditional advantage of much greater strength in all their joints thanthe ordinary blocks.

Y I have found it necessary to glue the boxwood face upon the end woodof the backing, because if it is put upon the side of a board theshrinkage of the box-wood face will inevitably spring up the ends of theboard, so that it will become warped and wholly unfit for use;consequently this end wood backing becomes the valuable anddistinguishing feature of my improvement.

I am aware that it has been a common practice to produce large blocks byjoining small blocks edge to edge with glue and bolts, and also that awood face has been used, secured upon the side of a board with glue orpins, for use in calico printing, and therefore I make no claim ofputting a face of wood upon the side of a board, nor for joining blocksedge to edge to produce larger ones 5 but i I do claim as my invention-The blocks herein described, for the purpose of wood-engraving, forletter-press printing, when these blocks are made by gluing a box-woodface upon the end grain of cheap -wood backing, so that the direction ofthe eEo. c. sETcHELL.l

. Witnesses:

WEBSTER PARK, `H. S. Corr.

